Cam for knitting machines



Aug. 9, 1938. R. H. LAWSON ET AL 2,126,645

l CAM FOR KNITTI-NG MACHINES Original Filed Jan. l0. 1934 3 Sheets-Sheet1 3 mientors.' EME/@7H A1/waxy Cttomeg Aug. 9, 1938.

R. H. LAWSON ET AL CAM FOR KNITIING MACHINES` Original Filed Jan. l0,1934 5 Sheets-Sheet 2 Patented Aug. 9, 1938 PATENT oFFicE CAM FORKNITTIN G MACHINES Robert H. Lawson and William L. Smith, Jr.,Pawtucket, R. I., assignors to Hemphill Company, Central Falls, R. I., acorporation of Massachusetts Original application January 10, 1934,Serial No.

I706,082. Divided and this application November 11, 1936, Serial No.110,353

6 Claims.

This invention relates to improvements in knitting machines and moreespecially, although not necessarily, to knitting machines having aplurality of feeding stations at each of which is a set of knittingcams. The case is a vdivision of co-pending application Ser. No.706,082, filed January l0, 1934, now Patent No. 2,067,877.

In the drawings:

Fig. l is a View in elevation showing a knitting machine to which theimprovements are applied;

Fig. 2 is a diagrammatic representation showing needles and jacks movingthroughout their respective pathways and being influenced by the severalcams;

Fig. 3 is a sectional View showing a needle and associated jack at acertain phase of the knitting cycle, said phase of the knitting cyclebeing indicated by line 3 3, Fig. 2;

Fig. 4 is a View in section showing the needle and jack at a later phasein the knitting cycle as indicated by the line 4 4, Fig. 2;

Fig. 5 is a relatively enlarged fragmentary View, partly in section,similar to Fig. 4 but showing the jack raising cam in tilted position;

Fig. 6 is a relatively enlarged fragmentary view, partly in section, andsimilar to Fig. 4;

Fig. 7 is a fragmentary plan View, partly in section of the parts shownin Fig. 6;

Fig. 8 is a View in section of the jack raising cam, the dotted linesrepresenting different paths of the jack butts;

Fig. 9 is a view similar to Fig. 8 but showing a slightly modifiedconstruction of the cam; and

Fig. 10 is a fragmentary View showing the advantages of the cam shown inFig. 9 as compared with the cam shown in Fig. 8.

Referring to Fig. 1, the frame I of the machine has mounted therein forrotary movements a needle cylinder 2 which may be rotated in anysuitable manner by driving mechanism (not shown), and, at times, by ahand wheel 3. Surrounding and supporting the needle cylinder 2 forrotary movements therein is a circular plate or base 4 which isconnected to the frame of the machine supported on legs 5. About theneedle cylinder 2 there have been spaced a plurality of cam supportingstructures or units 6, these units comprising the necessary cams foractuating needles and sinkers. Such cam supporting units are notnecessarily ofa type illustrated in this or the parent case, but may beof any suitable type such as employed in machines of this sort. Adjacentand preferably between each of the cam units has been secured aselecting device individual to each separate feeding station, suchselecting mechanism having a series of plungerlike instruments forfunctioning on one or more of a series of removable butts and a cam forengagement with aso-called master butt on instrumentalities which are tobe selected or caused to function in some desired way incidental to theknitting of patterned fabric. This selecting mechanism is generallyindicated at l.

A detailed description of this selecting mechanism is available in theparent case and will not be repeated here. The selecting instrumentswhich may be in the form of plunger-like elements manually movable toand from position to engage butts were claimed in that parent case andthe cam for engaging the so-called master butt to cause selectedinstrumentalities to be moved in some predetermined pathway will formthe subject matter of this case.

Now referring to Figs. 2, 3 and 4, one of these selecting plungers orelements is shown at B engaging a butt 9 on a jack I0. These butts 9 maybe frangible or movable in any desired manner, and jacks may have anyconvenient number of such butts. Said jacks I0 are further provided witha master butt II and another butt I2, this latter being for the purposeof returning jacks to non-selected position. Jacks are herein shown asworking beneath and upon needles I3 having the usual needle butts I4.Cam I5, one of which is to be provided as an essential adjunct to eachselecting unit works upon the master butt II in the event one of thejacks provided with such a butt is selected.

Needles pass through the cams of the machine being drawn down forknitting by one of cams I6, the pathway in which needle butts travelbeing indicated at I'I, this pathway varying as shown depending uponwhether or not a needlev is raised by one of the selecting jacks I0.These jacks move about the machine-in a pathway indicated at I8 for themaster butts II and at I9 for the butts I2 which, as before stated.return selected jacks to non-selected position. As shown, any one ofbutts 9 passing along in pathway 20 and encountering a plunger 3 whichis in butt engaging position, will be elevated sufficiently for itsmaster butt to engage and ride up cam I5 whereas if not selected, thatmaster butt would have passed along below said cam. Cams 2| maintainjacks at a predetermined low level and in alignment so that their butts9 will properly engage any selecting plungers 8 which are in positionwhile cams 22 return jacks to their initial position after being raisedby any one of cams I5. Needles the corresponding 4jacks of of themachine asbyscrews 39.

which are not selected will be iniiuenced by cams 23 only and will notbe raised to a latch clearing position nor will they take yarn at thatparticular feed. The pathway of such needles is indicated by numeral 24.Pathway 25 indicates the manner in which needles will be raised byselected jacks for clearing latches, taking yarnand knitting. Cams 25may be positioned at any desired feed for acting in conjunction with cam26' to knit continuously at that feed thus forming no pattern orornamental work thereat. Another cam such as 21 may be providedat-anyldesired feed for raising needles to a tuck position. The above isa brief descriptionfof the operation of the machine in the selection andcontrol of needles for knitting pattern `work and is nt`detailed innature since a complete and full disclosure is available in applicationSerial No. 706,082.

It sometimes happens when changingpa'tterns; i. e., re-selecting theplungers -8at the several feeding stations, that thefselected jacks, theselective butts 9 of which have-been partially elevated by plungers-,have elevated the lower-butts II -to a level intermediate their upperand lower positions. The effect of `such a relativepositioning of thelower ybutts II with respect to a cam I is illustrated-in Figs. 5-10inclusive. The lower butts IIv of the non-'selected jacks pass below thecam I5 when the needle cylinder 2 is again rotated atterra patternhas-been changed, the position of the said butts -being shown in Fig. 6and the path of the said butts -being also illustrated at 2B, Figs.8and9. Furthermore, the jacks thathave been -fullyraisedby the plungers8, upon resumption of'knitting move along a path 29, Figs. -8 andY 9.Accordingly the jacks whose butts upon resumption of knitting movealongpaths 281and 29- cause no trouble; however, the butts II that have,as just described, lbeen partially elevatedonly bythe withdrawn jackswhich were active in accordance with the previous pattern, uponresumption of knittingv will move along an intermediate-.path such as30, Figs. 8 and 9. Asknitting isresumed and thevneedle cylinderrecommences to rotate, such butts II move along the dotted line paths130, Figs. 8 and 9, towards the respective cams I5 or I5 andif the camI5 or the camI5 were-held ina rigidposition adjacentito the-needlecylinder the butts II advancingfalong the paths 3|] would strike thecamI I5 or I5,as the'case-may be, atlits leading edge but below theproper level 29 to=engage the upper face of the cam andi-be elevatedthereby; in-other words, the butts 1I I of such jacks'would be broken.To avoid any'such occurrence the cam lI5'is pivotally mountedso thatitmay be swungawayfrom the needle cylinderby a butt II advancingalong anintermediate path 30-as indicated in Fig. 5.

The cam I5 is -mounted uponcam plate 3| which is pivotally connected at32 to any upstanding bracket33 -whichis mounted upon and attachedr tothe circular plate 4 through plate 34. A coil spring 35 is connectedtothe upper end of the cam plate 3| at 36and atits other endis connectedto a block (not shown) for'to any suitable part of the machine, the saidspring serving to maintain the cam yyieldably in the position shown-inFig. 6. The movement of the cam I5ftoward the needle'cylinder is limitedby means of stop` screw or pin 3I which passes throughr an upwardlyextending arm "3B of a bracket which is fastened to the circular base 4YThe pin or screw 31 is locked in adjusted position as by means of asecond screw 40 which passes down wardly through the arm 38 and intocontact with the screw 3l.

Although the cam I5 shown in Fig. 8 is pivotally mounted as justdescribed to swing away from theneedle cylinder thus avoiding thebreaking of butts II, it is desirable that a butt the f jack of which isto select its needle for the new pattern, which but is adjacent to abutt travellingalong an intermediate path 30, be permitted uponresumption of knitting, to engage and be elevated by the upper face ofthe cam I5. This desirable object is not always attained when using thecam I5 having a straight, inclined surface such as shown in Fig. 8 andit is with the purpose of overcoming the possibility of certain of thebutts II not being elevated upon the resumption of knitting, that thecam I5 is used. Theadvantages inherent in the cam I5 as compared withthecam I5, will be obvious by inspection of Fig. 10. In this figure thedotted line represents the upper surface of the cam I5, Fig. 8, and thecurved line immediately adjacent thereto represents the upper surface ofthe cam I5. In the said Fig. 10 an intermediately positioned butt II isshown at 4I and an immediately adjacent butt II, the jack of which hasbeen selected according to the new pattern, is indicated at 42.

It will be evident that if the straight cam I5 be used and assuming thecam I5 to be in the position shown in Fig. 5, that the butt indicated at42 would pass back of the cam I5 before the said cam would be releasedto swing ,to a position adjacent to the needle cylinder such as shown inFig. 6, and as a consequence thereof the said butt-indicated at 42 wouldpass back of the cam and would hold the said cam in an outer positionwhich would also prevent adjacent and following butts II being elevatedby the cam I5. Now considering the cam I5 as indicated in Fig. l0 by afull line: the curving or cutting away of theupper face of cam I5adjacent to its leading end permits the immediately `following butt IIindicated at 42, to be engaged and elevated by the upper surface of thesaid cam I5'. In other words, the cutting away of the portion of the camI5 as compared with the cam I5 delays the interval of time which mustelapse-before a butt such as that indicated at 42 will be engaged andelevated.

It will be noted thatvthe leading edges-of the cams I5, I5' are curvedas at 43 thereby to permit the intermediately positioned butts II toswing thecam to the position shown in Fig. y5; otherwise the said buttswould be broken by the said leading edge of the cam.

This cam has been described in connection with a selecting mechanismparticularly adapted to multi-feed knitting machines and further,selecting mechanism involving manually controlled elements, however, inits broadest aspect the principles of the invention are to be applied toany knitting'machine wherein butts of the jacks or other knittinginstrumentalities are likely to strike the camin a manner to causedamage. The invention is dened in the appended claims.

We claim:

l. In a vknitting machine a cam adapted to be engaged by butts ofknitting instrumentalities thereby` to1actuate them, said cam beingpivotally supported to swing about a horizontal axis and yieldably heldin position adjacent to the needle cylinder, but being adapted to recedetherefrom upon vbeing engaged by a butt on one of the knittinginstrumentalities, a stop to limit movement of the cam in the directionof the needle cylinder.

2. Selecting means for knitting machines including in combinationknitting instrumentalities having a plurality of removable selectingbutts and a master butt, a cam for engagement with said master butt anda series of selecting elements for engagement with the selecting butts,the construction being such that said selecting elements if in positionto engage a selecting butt on an instrumentality will move it to aposition for engagement of its master butt with said cam, means wherebysaid cam may recede from active position so that upon withdrawal of anyselecting element, master butts left in a position to engage said camimproperly may pass without interference.

3. Selecting means for knitting machines including combination knittinginstrumentalities having a plurality of removable selecting butts and amaster butt, a, cam positioned for engaging master butts on selectedinstrumentalities but not to engage butts on those instrumentalitieswhich are notselected,a series of selecting elements movable to and -roma position to engage the selecting butts, the construction being suchthat an element in active position for engaging selecting butts willmove instrumentalities progressively to a position wherein their masterbutts will engage said cam, said cam having means thereon whereby itwill be maintained in position during normal operation of the machine,but allowing it to recede from that position in the event a master button an instrumentality which has been left in an intermediate positionupon withdrawal of any selecting element strikes the cam.

4. Selecting means for knitting mechines including in combination jackshaving a plurality of removable selecting butts and a master butt, a camfor engagement with master butts on jacks which have been selected, aplurality of selecting plungers for engagement with said selectingbutts, said plungers moving jacks having butts'thereon in a position tobe contacted by one of said plungers in active position to a positionwherein its master butt will engage and be controlled by the said cam,means for resiliently maintaining said cam in active position butallowing it to recede from that position upon contact of any master button a jack which has been left in an intermediate position uponwithdrawal of a plunger.

5. In a knitting machine a cam adapted to be engaged by butts ofknitting instrumentalities thereby to actuate them, said cam beingpivotally supported to swing in a vertical plane, means for holding saidcam in position to engage butts but allowing them to swing to a positionwherein butts may pass freely, and a stop for limiting movement of thecam in a direction to engage butts.

6. In a knitting machine a cam for engaging butts on knittinginstrumentalities, a vertically extending arm for supporting said cam, ahori- Zontal pivot about which said arm and cam may swing and springmeans for swinging said arm

